Critical Control

A control is something that is put in place to prevent, arrest, or mitigate unwanted events. A critical control is a control which:

• applies to an event that is considered critical to avoid, by way of being classified as a 'Material Unwanted Event' (MUE) or 'Priority Unwanted Event' (PUE), and failure of the control will result in a significant increase in risk, despite the presence of other controls

• controls for a multitude of unwanted events, some of which are MUEs/PUEs

An example of a critical control is a fire suppression system on an oil rig, because it satisfies the first criterion above.